This disclosure relates to an antenna unit for a vehicle. This disclosure is, more particularly, directed to mounting an antenna unit to a vehicle.
Known on-vehicle antenna units are installed on a metal pillar or on a metal roof of a vehicle by making a hole in the metal structure and then holding the antenna unit in place by using a nut screwed down in the interior of the vehicle. When the antenna unit is installed on the metal pillar or metal roof, the metal pillar or roof is in electrical contact with the vehicle frame, which is also metal, such that a ground is established between the vehicle and the antenna.
Where the antenna unit mounts to a dielectric panel, e.g., a glass or plastic panel, a problem occurs in grounding the antenna unit. It is known to mount an antenna unit to a dielectric panel; however, at present the assemblies used to mount the antenna unit to the vehicle fail to minimize or eliminate loads applied to the dielectric panel. Where the dielectric panel is glass, this can be especially problematic. Also, at present the assemblies used to mount the antenna unit to the vehicle also fail to accommodate for clearance variations between the dielectric panel and the vehicle frame.